Guide extension catheters (100) and methods of manufacturing and using guide extension catheters are disclosed. An example guide extension catheter may include a distal sheath (102) having a proximal opening (114), a distal opening (112), and a central lumen (116) extending therebetween. The guide extension catheter may also include a proximal shaft (104) having an outer diameter smaller than an outer diameter of the distal sheath, the proximal shaft including a distal opening (118). The guide extension catheter may also include a coupling member (106) for securing the distal sheath to the proximal shaft. The coupling member may include a distal portion (108) attached to the distal sheath and a proximal portion (110) disposed within the distal opening of the proximal shaft.
